Current understanding of the airborne transmission of important viral animal pathogens in spreading disease

Current research on airborne transmission of African swine fever virus (ASFV), porcine epidemic diarrhoea virus (PEDV), avian influenza (AIV), porcine reproductive and respira-tory syndrome virus (PRRSV), and foot and mouth disease virus (FMDV) was reviewed to evaluate commonalities, knowledge gaps, and methodologies of studying airborne trans-mission of animal diseases. The reviewed studies were categorised as short-range trans-mission (within a single facility) and long-range transmission (beyond a single site). Short-range airborne transmission was demonstrated for at least one strain of the above -mentioned pathogens in experimental settings. Most studies reported in the literature concern FMDV, with limited information for ASFV and PEDV, particularly for short-range airborne transmission. Air sampling upwind, downwind, and within infected facilities has been commonly used to demonstrate long-range airborne transmission. The amount of evidence from air sampling for each of the reviewed viruses varies from no evidence on ASFV to evidence from multiple settings for AIV. Computer modelling has been used to study past outbreaks of infectious diseases to assess the contribution of airborne trans-mission with a multitude of computer models reported in the literature for simulating long-range airborne transmission of FMDV based on past outbreaks. This has resulted in predictive tools for assessing future risk of airborne transmission. Some important com-puter models are based on epidemiology analysis, weather analysis, and air dispersion. Few models are reported for ASFV, PEDV, and PRRSV. Studies in the literature indicate that airborne transmission is generally affected by virus strain, aerosol type, shedding duration and concentration, environmental conditions, and infectious dose.(c) 2022 The Author(s). Published by Elsevier Ltd on behalf of IAgrE. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

This review summarizes current research on the airborne transmission of African swine fever virus, porcine epidemic diarrhea virus, avian influenza, porcine reproductive and respiratory syndrome virus, and foot and mouth disease virus. The studies are categorized into short-range transmission and long-range transmission. Short-range airborne transmission has been demonstrated in experimental settings for at least one strain of the mentioned pathogens. Most studies focus on foot and mouth disease virus, with limited information on African swine fever virus and porcine epidemic diarrhea virus. Air sampling is commonly used to demonstrate long-range airborne transmission. Computer modeling has been utilized to study past outbreaks and assess future risk of airborne transmission. The studies indicate that airborne transmission is influenced by virus strain, aerosol type, shedding duration and concentration, environmental conditions, and infectious dose.